Improvements in the dyeing of textiles



Patented Apr. 26, 1938 IMPROVEMENTS IN THE DYEING 6F TEX- TILES Karl Ott, Pavolding, and Otto Storb, Leverkusen- I. G. Werk, Germany, assignors to General Aniline Works, Inc., New York, N. Y., a corporation of Delaware No Drawing. Application August 9, 1935, Serial No. 35,530. In GermanyAugust'25, 1934.

9 Claims.

The present invention relates to a process for the dyeing of textiles.

n dyeing delicate tissues with certain vat dyestuffs, particularly such of the anthraquinone series, the mechanical properties, i. e. strength and resistance, of the textile fibers are often impaired, especially, if during the dyeing process they are repeatedly exposed to reduction and oxidation by the change between vat and air. Damages of the kind described are often met with when dyeing delicate tissues of artificial silk or cotton fabrics for a prolonged time on the reel vat or of yarns on Sellers machine.

We have now found that the said fabrics can be excellently protected against this injurious action of certain vat dyestufis by carrying out the printing or dyeing process in the presence of antioxidizing agents. As such agents preferably phenolic products being easily converted into quinones as, for instance, hydroquinone, have proved to be satisfactory. Instead of antioxidizing agents also such compounds may be employed which, during dyeing or printing, are transformed into antioxidizing agents. In this respect, for instance, quinones of the benzene and naphthalene series have proved to be suitable; their protecting effect probably being due to the fact,

that they are reduced by means of the react-' ing agents employed in the preparation of the 39 vat and then behave like antioxidizing agents. Besides hydroquinone or benzene quinone also naphthalene quinone suifonic acid, tannin and like substances have proved to be suitable. In most cases already a very small quantity of the 5 said protecting agents which may be used also in mixture with each other. will be suflicient in order to obtain the desired efiect. The protecting agents may be separately added to the dye bath or they can be incorporated with the dyestufi also ready before its use.

The following examples illustrate the inven- Example 1 A cotton fabric (Setaline) is dyed for 4 gs. of the 10% dyestufl paste 20 com. soda lye (38 Be.) 5 gs. of hydrosulflte. I

The dyeing is carried out at a temperature of 55 55 C. in the usual way and hydrosulfite an d lye are three hours on the reel with 20% of 2'3'6'7'-diphthaiicsubsequently added in the required amounts.

During the dyeing the fabric loses more than 50% of its strength. j

On repeating this experiment by adding 0,2 g. of tannin per liter to the dye bath, fabrics are obtained which have lost only 3,8% of their strength.

The same good result'is obtained on adding instead of tannin '2 'gs. of 1,4-naphthoic quinone If a. Setaline fabric is dyed with 20% of a 10% paste of 2'36'7'-diphthalic-n-ethyl-carbazo1e (s. Schultz-Julius, '1. Edn. No. 1286) in the presence of 0,2 g. hydroquinone per liter for three hours on the reel as described in Example 1, its strength practically remains unaltered. In contradistinction to the loss of 56,8% without the addition of hydroquinone, the strength is diminished only for 0,3%.

Instead of hydroquinone also 2 gs. of phenanthrene quinone per liter may be used with the same good result; both agents may also have been incorporatedwith the dyestufi before.

Example 3 A cotton fabric is dyed on the reel for three hours at 252 C. with 20% of a 10% paste of 1',2= dianthraquinonylamine (s. Schultz-Julius, 'l. Edn. Vol. I, No. 1249) The dye bath contains per liter 5 gs. oi the 10% paste of 1,2-dianthraquinonylamine, 8 gs. soda lye of 38 B. and 5 gs. of hydrosulflte'. The tensile strength of the dyed material is reduced for about On adding 0.1 g. of hydroquinone per liter to the dye bath or using a dyestufi paste containing the respective amount of hydroquinone and dyeing in the same way, fabrics are obtained which show an unaltered tensile strength.

Example 4 Mercerized cotton yarn is dyed on Sellers machine with a dye bath according to Example 1, containing 0.5 g. of tannin per liter. The strength of the yarn is unimpaired, whilst without the addition of tannin it is diminished for about 15-35%.

We claim:

1. The composition of matter containing as esaction during the dyeing process.

3. The composition 0! matter containing as essential ingredients a va't dyestufi' liable to damage celluloslc textile fibers during dyeing and hydroquinone.

4. The composition of matter containing as essential ingredients 9. vat dyestufl liable to damage cellulosic textile fibers during dyeingand a quinone.

5. The composition 0! matter containing as essential ingredients a vat dyestufi liable to damage cellulosic textile fibers during dyeing and naphthalene quinone suli'onic acid.

6. The composition oi matter containing as essential ingredients a vat dyestufi liable to damage cellulosic textile fibers during dyeing. and tannin.

-'7. In the process of dyeing textile materialwith a vat dyestufi' liable to damagecellulosic textile fibers during dyeingythe step which comprises dyeing inthe presence of hydroquinone. 8. In the process oi dyeing textile material with a vat dyestufl. liable to damage. cellulosic textile fibers durihB' dyeinl. the step which comprises dyeing in the presence of a quinone.

9. In the process of dyeing textile material with a vat dyestufi' liable to damage cellulosic textile fibers during dyeing, the step which com prises dyeing in the presence 01 tannin.

o'rro .BTORB. 

